Flow microfluorometers which are valuable in many areas of biological research typically use a laser as an excitation source and collect about 2.5% of the total cell fluorescence using standard optics. There is an existing need for advanced instrumentation so that more demanding biological studies can be undertaken. Among these are the detection of life from bioluminescent reactions, quantitative human karyotyping, and determining the DNA content of peripheral lymphocytes for genetic analysis. Such advanced instruments will provide increased resolution, increased light collecting efficiency, and increased system versatility and applicability utilizing broad band emitting, i.e., 250-1000 nanometer (nm) light sources.
One advanced instrument is that described in U.S. Pat. No. 3,946,239 to Salzman et al. This patent is directed to a cell flow system utilizing an ellipsoidal flow chamber having light reflective walls and providing greatly increased signal-to-noise ratios over those obtained by prior art systems. The ellipsoidal cell flow system provides enhanced resolution particularly valuable for viewing weakly fluorescent particles such as bacteria and asymmetric particles such as chromosomes and mammalian cells.